NPP Check Engine Light (CEL)
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Joined: Jan 2023
Posts: 83
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From: SE Michigan
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NPP Check Engine Light (CEL)
I'm getting a CEL for NPP exhaust valve stuck.
The first time it happened, I had pulled into the dealer to have the look and the pass seat belt (locking Issue). Anyway when he started it with the OBD II reader, CEL came on. He cleared it and I went on my way. Happened a couple more times now, and I figured out want causes it. If I'm in Z mode, the car is warm, shut it off and restart with in 15 mins or so it comes on then goes away after a few ignition cycles. I think this is because if you shut the car off in Z moce it comes back on in Tour and quiet exhaust.
All that for my question. Does anyone know what is involved it changing the exhaust valve? Not sure I want to deal wiht it if they have to take the bumper off. I never use tour or weather. If the Option was loud or quiet exhaust I would have picked loud.
The first time it happened, I had pulled into the dealer to have the look and the pass seat belt (locking Issue). Anyway when he started it with the OBD II reader, CEL came on. He cleared it and I went on my way. Happened a couple more times now, and I figured out want causes it. If I'm in Z mode, the car is warm, shut it off and restart with in 15 mins or so it comes on then goes away after a few ignition cycles. I think this is because if you shut the car off in Z moce it comes back on in Tour and quiet exhaust.
All that for my question. Does anyone know what is involved it changing the exhaust valve? Not sure I want to deal wiht it if they have to take the bumper off. I never use tour or weather. If the Option was loud or quiet exhaust I would have picked loud.
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From: Ft Lauderdale
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you really shouldn’t be too afraid of them taking the back bumper off. There are several tubes on it, , it’s just a matter of finding all the bolts and it really slides off. I’ve got it scheduled to do in the next couple months as I’m gonna mount an AWE exhaust…
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Since you prefer your car loud, couldn't you set the exhaust in My Mode to sport or track? Put your car in My Mode. As long as you turn Z Mode off before shutting off your car, it'll start back up in My Mode, the valves wouldn't close.
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Joined: Jan 2014
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From: Fulshear, TX
The valves are always moving, even when in Z/Track, to control the undesirable boomy drone. Warranty will get the OP all sorted out.
